Self-healable and Robust Film Based on Electroactive Polymer Brush as Electrode for Flexible Supercapacitor

The aim of this study was to develop self-healable and robust electroconductive film based on polyaniline copolymer for application as electrode in flexible supercapacitor. For this purpose, the electroconductive polymer brushes (EPB) was elaborated. The synthesis of EPB is based on graft polymerizations of acrylamide (AAm) on poly(vinyl alcohol) (PVA) with formation of PVA-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on PVA-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-p-phenylenediamine) (PAPhDA). It was found that the ratio between PVA and PAAm at the first stage greatly influence the electrochemical performance of the EPBs. Electroconducting films were prepared by casting of EPB solution with subsequent drying. Investigation of electrical current distribution through the film with AFM reveal more uniform distribution of PAPhDA in EPB in comparison with reference PVA-PAPhDA and PAAm-PAPhDA samples. It was demonstrated that mechanical characteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level (58%). The flexile supercapacitor cell with EPB film electrodes demonstrate specific capacitance 602 mF·cm⁻² at the current density of 1 mA·cm⁻² and retention 94% of initial capacitance after 5000 charge/discharge cycles.